Refrigerating machine



Aug. 11, 1936. H, HJBIXLER REFRIGERATING MACHINE Filed Sept. 24, 1955 Inventor; Harlepg HtBxler, 7W 'SMZM b5 HsAttornedg.

Fatented ug. 1i, i936 NETE STAT S PAT 2,050,876 REFRIGERATING MACHINE New York Application September 24, 1935, Serial No. 41,905

9 Claims.

My invention relates to refrigerating machines. Refrigerating machines of the compression type usually include a refrigerant compressor in which a Vaporized refrigerant, such as methyl formate, 54 is compressed and which then ows to a condenser where it is liquefied. The liqueed refrigerant is supplied to an evaporator through a float valve or other flow controlling device. The interior of the evaporator is maintained at low pressure by the compressor and the absorption of heat by the liquid refrigerant in the evaporator causes the same to vaporize, the Vaporized refrigerant being then returned to the compressor. This cycle is continued until the temperature of the compartment in which the evaporator is located is lowered to the desired value. Diculty has been' encountered in the operation of such refrigerating machines in that gases, which are non-condensable at pressures and temperatures encountered in an ordinary refrigerating machine, sometimes become mixed with the refrigerant. This may result when methyl chloride is used as the refrigerant, for example, due to the partial disintegration 0f the methyl formate into carbon monoxide and carbon dioxide, each of these latter gases being noncondensable at ordinary pressures and temperatures had in a refrigerating machine. Such non-condensable gases collect in the condenser and oat valve casing. or other liquid refrigerant receiver chamber and tend to prevent the normal condensation of the compressed vaporized refrigerant.

It is an object of my invention to provide an arrangement in a refrigerating machine of the type described for preventing the collection of noncondensable gases in the condenser thereof.

Another object of my invention is to provide an improved arrangement for inducing a rapid circulation of refrigerant through the condenser of a refrigerating machine of the type described.

Another object of my invention is to provide for the carrying out of a method of operation of a refrigerating machine in such manner as to prevent the static accumulation of non-condensable gases inthe system which would interfere with its operation.

Further objects and advantages of my invention will become apparent as the following description proceeds, and the features of novelty which characterizes my invention are pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of my invention reference may be had to the accompanying draw- 55 ing, in which Fig. l is a side elevation partly in Civ section of a refrigerating machine of the household type embodying my invention, and Fig. 2 is a side elevation partly in section of a modified form of refrigerating machine of the household type embodying my invention. 5

Referring to the drawing, I have shown in Fig. 1 a refrigerating machine designed for household use which includes a rotary type compressor I0, which is connected to a vertical driving shaft II of an electric driving motor I2. Vaporized re- 10 frigerant compressed by the compressor I0 is liquefied in a natural draft air-cooled condenser I3 and is then supplied through a now-controlling float Valve located in the float valve casing I4 to a flooded type evaporator I5. The liquid 15 refrigerant in the evaporator I5 is Vaporized by the absorption of heat from the contents of the compartment in which the evaporator is located, and the refrigerant thus Vaporized is returned to the compressor I 0. The entire refrigerating ma- 20 chine is supported on a removable heat-insulated top Wall I6 of the compartment in wihch the evaporator I5 is located.

The compressor I0 is supported in a cylindrical hermetically sealed casing I1, made of steel 25. or the like, on a series of vertical helical compression springs I8. The casing I'I includes complementary upper and low sections I9 and 20, respectively, the adjacent edges of which are welded together in abutting relation as indicated at 2|. 30 A reinforcing strip 22 is positioned within the casing Il and covers the inner side of the Welded seam 2I. The compressor I0 is provided with an integral open top supporting casing 23 on the top thereof, which supports the electric driving motor 35A I2. A series of horizontal feet 24 extend laterally from the sides of the supporting casing 23 and the tops of the supporting springs I8 are secured thereto by suitable plugs and bolts 25.

Vaporized refrigerant, such as methyl formate, 40 is compressed by the refrigerant compressor Il) and is discharged therefrom through a suitable discharge port thereof into the interior of the casing I'I. The gaseous refrigerant in the casing Il ows therefrom through a conduit 26 which 45 communicates with the interior of the casing and with the refrigerant circulatory passages of the condenser I3. The condenser I3 is cylindrical in shape 'and surrounds the casing I1, being made up of complementary cylindrical sheets of metal 21 and 28. A refrigerant circulatory passage 29 is formed between the inner and outer sheets 27 and 28 by complementary indentations 30 and 3l formed therein. The refrigerant circulatory passage 29 is preferably divided into upper and lower 5:

sections which are connected in series by a U- shaped conduit 32. The inner and outer sheets are rigidly secured together by line welding, a

series of closely spaced spot welds, or otherwise,

about the edges thereof and between the indentations 30 and 3l formed therein throughout the length of such indentations. The condenser I3 thus formed is supported on a series of radial heat-conducting ns 33 which extend between the outer side walls of the casing I1 and the inner walls of the condenser I3. Cooling air circulates upwardly over the surfaces of the condenser I3 and ns 33 due to natural draft, and the refrigerant circulating through the passage 29 is cooled thereby and liquefied. The refrigerant thus liquefied in the condenser I3 ilows` therefrom through a conduit 34 to the casing or chamber I4 in which a flow-controlling float valve is located.

I provide an arrangement for conveying the vaporized refrigerant or other fluid within the casing I1 through the conduit 26 and condenser I3 independently of the pressure prevailing in the casing I1. As illustrated in Fig. 1 a centrifugal fan 35 is secured to the upper end of thev vertical driving shaft II of the electric motor I2 and is driven thereby. The inner end of the conduit 26 is located closely adjacent the periphery of the centrifugal fan 35 and, as a consequence, fluid within the casing I1 is blown into the conduit 26 upon rotation of the fan 35. Refrigerant is thus positively and rapidly circulated through the refrigerant circulatory passage 29 of the condenser I3, and the heat transfer between the refrigerant flowing through the condenser I3 and the cooling air flowing over its surfaces is improved. The fan 35 also serves to circulate compressed gaseous refrigerant or other fluid within the casing I1 over the surfaces of the compressor IIl and driving motor I2. This circulation of iluid over the surfaces of the compressor and driving motor serves to transfer heat therefrom to the walls of the casing I1 from which it is dissipated to the surrounding cooling air circulating thereover due to natural draft. The fan 35 thus serves the double purpose of cooling the compressor I0 and driving motor I2 therefor, and circulating refrigerant through the condenser I3.

I also provide an arrangement for conveying non-condensable gases from the float valve casing i I4 to the interior of the hermetically sealed casing I1. Gases which are non-condensable at the pressures and temperatures ordinarily encountered in a refrigerating machine are frequently mixed with the methyl formate, or other vaporizable refrigerant, in the machine. Such noncondensable gases may be formed in the machine due to the disintegration of the refrigerant. In the case of methyl formate it has been found that carbon monoxide and carbon dioxide are frequently formed after the refrigerant has been used for some time in the refrigerating machine. As a consequence, the casing I1 ordinarily contains a fluid mixture of compressed vaporized refrigerant and non-condensable gases. If some provision is not made for returning the noncondensable gases to the `compressor IG from the float valve casing IQ, they will accumulate in the condenser I3 and in the float valve casing I4 until the condenser is partially or wholly filled by such non-condensable gases, thus obstructing the o'w of liquid refrigerant and seriously impairing the liquefying action of the condenser.

In the form of my invention illustrated in Fig. 1 a conduit 35 is provided which communicates with the interior of the float valve casing I4 above the normal liquid level therein, which is indicated by dot-dash line 43, and with the lnterior of the hermetically sealed casing I1 above the level of the lubricating oil 35a. in the bottom thereof. The float valve casing I4 thus receives liquefied refrigerant and non-condensable gases flowing from the condenser I3 and they are separated by gravity in the float valve casing. The non-condensable gases which collect above the normal level of the liquid refrigerant in the float valve casing I4 flow upwardly through the conduit 35 into the casing I1. Since the casing I1 is of much greater cubic capacity than the refrigerant circulatory passage 29 of the condenser I3, an undue concentration of non-condensable gas is not had in the casing I1. Also, since the fan 35 continuously circulates refrigerant and non-condensable gases through the condenser I3, the non-condensable gases do not have an opportunity to collect therein but 'are moved rapidly therethrough and returned to the casing I1 through the conduit 35. By this arrangement I am enabled to carry out a method of operating the refrigerating machine such that non-condensible gases will not accumulate in the condenser 29 of the machine and prevent the flow of compressed refrigerant thereto during operation of the machine.

The liquefied refrigerant accumulated in the float valve casing I4 is supplied therefrom through a conduit 36 to the refrigerant circulatory passages formed by indentations 31 in an outer sheet of the sheet metal evaporator I5. The evaporator I5 is made up of inner and outer sheets of metal which are welded or otherwise rigidly secured together about the edges thereof and between the indentations formed therein,

and a cylindrical longitudinal header 38 is formed in the upper portion of the evaporator I5. The upper ends of the passages formed by the indentations 31 communicate with the header 38 below the normal liquid level therein, the header 38 being ordinarily maintained about half full of liquid refrigerant. The liquid refrigerant in the flooded evaporator 'I5 is vaporized by the absorption of heat from the contents of the compartment in which it is located, and the refrigerant thus vaporized is collected in the header 38 above the level of the liquid refrigerant therein. The vaporized refrigerant thus collected in the header 38 is returned to the intake port of the compressor I0 through an exhaust conduit 39. The cycle of operation described above is repeated and continued until the temperature of the compartment in which the evaporator I5 is located is lowered to a desired value.

The refrigerating machine shown in Fig. 2 embodying my invention is similar to that shown in Fig. l, and the same numerals have been used to designate identical parts. In the arrangement shown in Fig. 2 a rotary type compressor I0 is provided with an upwardly extending casing 23 on which an electric driving motor I2 therefor is mounted. The compressor I0 and driving motor I2 are mounted within a cylindrical hermetically sealed casing I1 made up of upper and lower sections I9 and 20, respectively, on a series of vertical helical compression springs I8. The upper and lower sections I9 and 20 of the hermetically sealed casing I1 are welded together at 2l and a reinforcing strip 22 is provided within the casing I1 and extends about the inner side of the seam 2I. The upper ends of the supporting springs I8 are secured to laterally projecting feet 24 formed on the casing 23 by suitable bolts and plugs 25.

Vaporized gaseous refrigerant compressed in the compressor I1 passes from the discharge port thereof through a conduit d, the upper end @I of which communicates with the interior of the hermetically sealed casing I1. Compressed vaporized refrigerant within the casing I1 passes therefrom through a conduit 26 into the refrigerant circulatory passage 29 of the condenser I3 which surrounds the casing I1.

'I'he condenser I3 is made up of complementary cylindrical inner and outer sheets of metal 21 and 28 having complementary indentations 30 and 3l, respectively, formed therein. The indentations 30 and 3| define a refrigerant passage 23, and the sheets 21 and 28 are welded or otherwis rigidly secured together about their edges and between th indentations formed therein throughout their length. The refrigerant circulatory passage 29 is preferably divided into upper and lower sections which are connected in series by a conduit 32. The condenser I3 thus formed is supported on a series of radial heat-conducting fins 33 which extend between the outer side walls of the casing i1 and the inner Walls of the condenser I3. The compressed vaporized refrigerant passing through the refrigerant circulatory passage 23 of the condenser I3 is cooled and liquefied by the transfer of heat therefrom to the cooling air which circulates upwardly over the surfaces of the condenser I3 and ns 33 due to natural draft. The refrigerant thus liquefied in the condenser I3 flows therefrom through a conduit 34 to a float valve casing or chamber Ill in which it is accumulated.

A conduit 35 is provided which communicates with the interior of the float valve casing I4 above the normal liquid level therein, indicated by the dot-dash line 43, and with the interior of the hermetically sealed casing I1 above the level of the lubricating oil 35a accumulated in the lower portion thereof.

I provide an arrangement for inducing a flow of the flud mixture of vaporized refrigerant and non-condensable gases in the casing I1 through the condenser I3. In the form of my invention illustrated in Fig. 2 the inner end of the' conduit 26 is provided with a flared or funnel-shaped end portion 42 which surrounds the open upper end 4I of the compressor discharge conduit 40. The vaporized refrigerant compressed by the compressor I0 and discharged therefrom through the conduit IIB escapes in a stream from the outer end 4I of the conduit 40 at relatively high speed and enters the condui't 26. The stream of compressed gaseous refrigerant discharged from the conduit 4D into the conduit 26 entrains a portion of the fluid mixture of compressed vaporized refrigerant and non-condensable gases in the casing I 1 and draws the same through the funnelshaped end 42 of the conduit 26. The non-condensable gas and refrigerant in the condenser I3 are thus rapidly circulated therethrough due to the injector action of the compressor discharge conduit 40, and the non-condensable gas which collects in the float valve casing I4 above the normal liquid level therein is returned to the casing I1 through the conduit 35 due to the fluid circulation set up by the stream of compressed vaporized refrigerant discharged into the conduit 26.

The liqueed refrigerant accumulated in the float valve casing I4 is supplied therefrom through a conduit 36 to the refrigerant circulatei-y passages formed by indentations 31 in an evaporator I5 is vaporized by the absorption of heat from the contents of the compartment in which it is located, and the refrigerant thus vaporized is collected in the header 38 above the level of the liquid refrigerant therein. The vaporized refrigerant collected in the header 38 is returned to the intake port of the compressor IU through a conduit 39. The cycle of operation above described is repeated and continued until the compartment in which the evaporator I5 is located is lowered to a desired value.

It will thus be seen that I have provided an improved method and arrangement by means of 25 which an accumulation of non-condensable gases in the refrigerant circulatory passages of the condenser is prevented. As a consequence the condenser is able to operate eiciently and its passages will not become clogged with non-condensable gases.

Although I have illustrated two particular forms of my invention in connection with household type refrigerating machines, I do not desire my invention to be limited to the particular embodiments shown and described, and I intend in the appended claims to cover all modifications within the spirit of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. A refrigerating machine comprising a refrigerant compressor, a refrigerant condenser, means for supplying compressed vaporized refrigerant from said compressor to said condenser, means including a chamber for accumulating vaporizable liquid refrigerant liquefied in said condenser and non-condensable gases leaving said condenser, means communicating with said chamber above the normal liquid level therein for conveying non-condensable gases from said chamber and for mixing the non-condensable gases with compressed vaporized refrigerant leaving said compressor, means utilizing the flow of refrigerant from saidcompressor to said condenser for inducing a iiow of non-condensable gases from said chamber to the means supplying compressed refrigerant to said condenser, a refrigerant evaporator, and means for supplying liquid refrigerant accumulated in said chamber to said evaporator.

2. A refrigerating machine comprising a hermetically sealed casing, a refrigerant compressor mounted in said casing, a refrigerant condenser,

means for supplying compressed vaporized refrigerant from said compressor to said condenser,

means including a chamber for accumulating vaporizable liquid refrigerant liquefied in said condenser and non-condensable gases leaving said condenser, means communicating with said chamber above the normal liquid level therein 7@ for returning non-condensable gases from said chamber to said casing, means utilizing the flow of refrigerant from said compressor to said condenser for inducing a flow of non-condensable gases from said chamber to the means supply- .5 n

' denser, means for supplying the fluid mixture in metically sealed casing,

said casing to said condenser, means including a chamber for accumulating vaporizable liquid refrigerant liquefied in saidcondenser and noncondensable gases leaving said condenser, means communicating with said chamber above the normal liquid level therein for returning non-condensable gases from said chamber to said casing, means utilizing the flow of refrigerant from said compressor to said condenser for inducing a flow of non-condensable gases from said chamber to the means supplying compressed refrigerant to said condenser, a refrigerant evaporator', and means for supplying liquid refrigerant accumulated in said chamber to said evaporator.

4. A refrigerating machine comprising a hermetically sealed casing, a refrigerant compressor mounted in said casing, a refrigerant condenser, means for supplying compressed vaporized refrigerant from said compressor to said condenser, means including a float valve and a casing therefor for accumulating vaporizable liquid refrigerant liquefied in said condenser and non-condensable gases leaving said condenser, means communicating with said iioat valve casing above the normal liquid level therein for returning. noncondensable gases from said iioat valve casing to said hermetically sealed casing, means utilizing' the flow of refrigerant Afrom said compressor to said condenser for inducing a fiow of non-condensable gases from said float valve casing to said hermetically sealed casing, a refrigerant evaporator, and means for supplying liquid refrigerant accumulated in said float valve casing to said evaporator. i

5. A refrigerating machine comprising a hera refrigerant compressor mounted in said casing, said compressor being provided with intake and discharge ports, said discharge port of said compressor communicating with the interior of said hermetically sealed casing, said hermetically sealed casing containing a fluid mixture of compressed vaporized refrigerant and non-condensable gases, a refrigerant condenser, means for supplying the uid mixture from said hermetically sealed casing to said condenser, means including a float valve and a casing therefor for accumulating vaporizable liquid refrigerant liquefied in said condenser and non-condensable gases leaving said condenser, means communicating with said float valve casing above the normal liquid level therein for returning said non-condensable gases from said float valve casing to said hermetically sealed casing, and means utilizing the flow of refrigerant from said compressor to said condenser for inducing a flow of non-condensable gases from said float valve casing to said hermetically sealed casing.

and said chamber.

6. A refrigerating machine comprising a hermetically sealed casing, a refrigerant compressor mounted in said casing, a driving motor for said compressor having a vertical shaft positioned above said compressor in said casing, said compressor having intake and discharge ports, said discharge port of said compressor communicating with the interior of said casing, a refrigerant condenser, 'means including a conduit for conveying compressed vaporized refrigerant from the interior of said casing to said condenser, and means including a cooling fan secured to the upper portion of said shaft of said driving motor and positioned in said casing and a conduit opening at the periphery of said fan for positively circulating vaporized refrigerant fromfthe interior of said casing through said conduit and said condenser and for circulating cooling fluid over the surfaces of said motor and compressor.

7. A refrigerating machine comprising a hermetically sealed casing containing a fluid mixture of compressed vaporized refrigerant and non-condensable gases, a refrigerant compres- Vsor mounted in said casing, said compressor having intake and discharge ports, a refrigerant condenser, a conduit communicating with said condenser and with said casing, said conduit having a funnel-shaped end located within said casing, and means conveying compressed vaporized refrigerant fronrsaid compressor discharge port to said funnel-shaped end of said conduit for inducing a flow of the fiuid mixture from said casing through said conduit and said condenser.

8. A refrigerating machine comprising a hermetically sealed casing containing a fluid mixture of compressed vaporized refrigerant and noncondensable gases, a refrigerant compressor mounted in said casing, said compressor having intake and discharge ports, a refrigerant condenser, a conduit communicating with said condenser and with said casing, said conduit having a funnel-shaped end located within said casing, means conveying compressed vaporized refrigerant from said compressor discharge port to said funnel-shaped end of said conduit for inducing a flow of the iiuid mixture in said casing through said conduit and said condenser, means including a chamber for accumulating vaporizable liquid refrigerant ligueiied in said condenser and noncondensable gases leaving said condenser, and means communicating with said chamber above the normal liquid level therein for returning noncondensable gases from said chamber to said casing.

9. In a refrigerating machine having a hermetically sealed casing enclosing a compressor and containing a substantial quantity of non-condensable gas together with refrigerant discharged from said compressor, a condenser receiving compressed refrigerant from said casing, a chamber receiving liquefied refrigerant from said condenser and conmrunicating above the normal level of liquid refrigerant therein with said casing, a method of lpreventing the accumulation of noncondensable gases in said condenser which comprises circulating refrigerant and non-condensable gases through said casing, said condenser HARLEY H. BIXLER. 

